blessing



(No Model.)

J. H. BLESSING. PISTON FOR STEAM ENGINES.

Patented May 5, 1891.

RWY c027:

L/AMES H BLESuSI/VG.

UNITED STATES ATENT JAMES H. BLESSING, OF ALBANY, NElV YORK.

PISTON FOR STEAM-ENGINES.

SPECIFICATION formingpart of Letters PatentNo. 451,850, dated May 5, 1891.

Application filed November 22,1890. Serial No. 372,320. (No model.)

To all whom it may concern.-

Be it known that 1, JAMES H. BLEssING, of the city and county of Albany, in the State of New York, have invented new and useful Improvements in Pistons for Steam-Engines, Pumps, &c., of which the following is a full and exact description, reference being had to the accompanying drawings, which form part of this specification, and in which Figure 1 is a side elevation of a piston embodying my invention. Fig. 2 is an end elevation of the same with the follower removed. Fig. 3 is avertical section of Fig. 2 at the line X X. Fig. 4 is a perspective View of the packing detached from the piston, a section of the same being removed for the purpose of exposing underlying parts. Fig. 5 is a perspective view of the piston and follower separated from each other, and Fig. 6 is a perspective view of the piston-head detached from the piston-rod.

My invention relates to improvements in pistons for steam-engines, pumps, and other machines of like character; and it consists of the novel construction herein described, and pointed out in the'claims. r

As represented in the drawings, A indicates a piston-rod of an ordinary and well-known form; B, a piston-head fitted thereon and provided with a boss 1, which may be integral with said piston-head, 01', if preferred, made separable therefrom. Said boss is preferably made in a cylindrical form and its bore is made to fit the piston-rod snugly.

O designates the follower for the piston, made in the form of an annulus and having a central opening 2, which fits on the pistonrod A. Said follower is fitted to bear against the end of the boss 1, and is secured in place by means of a nut 3, which is fitted to screw onto the corresponding extremity of the pis ton-rod A.

D designates a cubiform center, which is preferably made separately from the pistonhead B, and is provided with a central opening 4., which fits loosely over the boss 1, so as to allow a slight free play of said boss in the central opening to compensate for any possible difference between the central line of the cylinder and the line of the movement of the piston-rod, whether said difference arises from defective workmanship or from the eifect of wearing. The center D is provided with transverse openings 5, which are arranged parallel to the sides of said center, which range in line with the central opening 4. Two of said transverse openings are arranged on one plane to run in one direction through said center, and the other two openings are arranged on another plane to run at right angles to the first two. Each of the openings 5 contains a spring 6 for the purpose of forcing the parts of the piston-packing outwardly into close contact with the bore of the cylinder in which it is fitted.

E designates the piston-packing, which is formed of 'semicirc ular metallic plates '7, fittedtogether in layers, so that the straight edges of said plates will meet, or nearly so, to form joints that will correspond with the diametrical line of the piston. As shown in the drawings, said packing is composed of two layers of said plates; but a larger number of layers may be used, if required, and each layer is formed of two of said semicircular plates joined as above described. Said plates are made so that their convex edge will conform to the bore of the cylinder. Each of said plates has in its straight or diametrical edge a rectangular recess 8, which is fitted to engage on the center D in such manner that the straight edge of the plate can reach to the diametrical line of the piston. Vhen the packing is to be used on the pistons of either steam-engines or hot-water pumps, each of the semicircular plates 7 has slots 9 out therein to extend from its straight edge toward its convex edge. Preferably said slots are cut at right angles to the face of the straight edge of the plate, and they extend nearly to the convex edge, thereby leaving a moderately thin neck or connection 10 at the inner termination of each slot, so as to afford sufficient elasticity at those points to compensate for a lengthwise elongation of the plate when affected by heat. WVhen the packing is to be used on the pistons of cold-water pumps or for other purposes where it will not be subjected to heat, the slots 9 can be omitted from the semicircular plates 7. The diametrical joints between each pair of the semicircular packing-plates are so arranged that the joints of the different layers will be at rightangles to the joints of the next layer, and so. that the solid part of the plates of one layer Will cover and form a break-joint for the joint of the next layer.

lVhatIclaim as my invention, and desire to secure by Letters Patent, is

1. A piston composed of a head having a cylindrical boss, a follower for said head, a cubiform center fitted to slip on said boss and provided with springs arrangedin transverse pairs, and a piston-packing formed of semicircular plates whose straight edge is provided with a rectangular recess that is fitted to engage on said cubit'orin center, said packing-plates being arranged in layers so that the diametrical joint of one layer Will be at right angles to the like joint of the next layer, as and for the purpose herein specified.

2. A piston composed of a head having a cubiforin center, which is provided with springs arranged in transverse pairs, a follower for said head, and a piston-packing formed of semicircular plates Whose straight edge is provided with a rectangular recess that is fitted to engage on said cubiform center, said packing-plates being arranged in layers so that'the diametrical joint of one layer will be covered by the solid part of the next layer, as and for the purpose herein specified.

3. A piston composed of a head having a cubiforni center, Which is provided With springs arranged in transverse pairs, a follower for said head, and a piston-packing formed of semicircular plates Whose straight edge is provided with a rectangular recess that is fitted to engage on said cubiform center, and having slots which extend from the straight edge toward the convex edge of the plates, said packing-plates being arrangedin layers so that the diametrical joint of one layer Will be covered by the solid part of the next layer, as and for the purpose herein specified.

JAMES II. BLESSING.

Witnesses:

JOHN W. WHEELocK, WM. H. Low. 

